Brin took the incident personally. Insiders observed he was much less perturbed by the theft of Google's intellectual property than the fact that his company had unwittingly been a tool used to identify and silence critics of a repressive government. Brin wanted the incident to be the catalyst to the action that he and others had been urging since 2008: Google should stop censoring. He was passionate in his insistence. He had support from some executives who had soured on China over the past 10 months -- but not all. Notably, Schmidt was not convinced. But Brin was adamant: Google was under attack by the forces of evil, and if his fellow executives did not see things his way, they were supporting evil.

That's when Brin threatened to quit if Google didn't take action, according to Levy's source.

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Brin hasn't denied that he was willing to walk away, but he told Levy he doesn't remember the threat.

Levy: "Brin, through a spokesperson, didn't recall saying that, and said that the company was so much in his blood and DNA, it was unlikely that he expressed that intention. He did acknowledge that during the many hours of debate, he presented his case with utmost passion."